Studies in the area of periodontal disease have defined the crucial factors involved in the inflammatory process including; 1) the role of neutrophils; 2) the role of lipid mediators; 3) identification of bacterial processes in amplifying the inflammatory condition; and 4) the role of the hosts innate and humoral immune systems. In support of projects 1-4, and to optimize, centralize and facilitate the discovery of novel, topically active anti- inflammatory and anti-PMN analogues of naturally occurring lipid mediators; this Core will provide and apply established in vivo animal, cellular and organ models, as well as carry out in vitro assays to: a) assist in the discovery of structure/function relationships of novel, topically occurring anti-PMN and anti-inflammatory compounds generated in Projects 1-4 and establish their actions in vivo in wild type and genetically altered rabbits. b) provide flow cytometric analysis of cells from Project 1-4. c) provide PMN functional assays in vitro and in vivo. d) provide and develop animal and cellular models/assays for the evaluation of novel therapeutics in periodontitis. Providing a centralized location of these routine tasks to this Core will eliminate costly duplication of these assays/models within the other projects. This Core will optimize productive interactions and resource utilization and provide the other projects with efficient and timely access to novel. Prioritization of the provide the other projects with efficient and timely access to novel cell and in vivo assays. Prioritization of the assays/models will be accomplished through individual meetings between Core D's principal investigators and the Program Project principal investigators and during monthly meetings of the Program Project team. Centralization of these models and assays will facilitate the demonstration and the effectiveness of these novel therapeutics in periodontal disease.